# coding=utf-8
# Copyright 2023 Microsoft Research and The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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"""PyTorch KOSMOS-2 model."""

import math
from collections.abc import Callable
from dataclasses import dataclass
from typing import Any, Optional, Union

import torch
from torch import nn

from ... import initialization as init
from ...activations import ACT2FN
from ...cache_utils import Cache, DynamicCache, EncoderDecoderCache
from ...generation import GenerationMixin
from ...modeling_flash_attention_utils import FlashAttentionKwargs
from ...modeling_layers import GradientCheckpointingLayer
from ...modeling_outputs import (
    BaseModelOutput,
    BaseModelOutputWithPastAndCrossAttentions,
    BaseModelOutputWithPooling,
    CausalLMOutputWithCrossAttentions,
)
from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from ...processing_utils import Unpack
from ...utils import ModelOutput, TransformersKwargs, auto_docstring, can_return_tuple, logging, torch_int
from .configuration_kosmos2 import Kosmos2Config, Kosmos2TextConfig, Kosmos2VisionConfig


logger = logging.get_logger(__name__)


def _expand_mask(mask: torch.Tensor, dtype: torch.dtype, tgt_len: Optional[int] = None):
    """
    Expands attention_mask from `[bsz, seq_len]` to `[bsz, 1, tgt_seq_len, src_seq_len]`.
    """
    bsz, src_len = mask.size()
    tgt_len = tgt_len if tgt_len is not None else src_len

    expanded_mask = mask[:, None, None, :].expand(bsz, 1, tgt_len, src_len).to(dtype)

    inverted_mask = 1.0 - expanded_mask

    return inverted_mask.masked_fill(inverted_mask.to(torch.bool), torch.finfo(dtype).min)


def _make_causal_mask(
    input_ids_shape: torch.Size, dtype: torch.dtype, device: torch.device, past_key_values_length: int = 0
):
    """
    Make causal mask used for bi-directional self-attention.
    """
    bsz, tgt_len = input_ids_shape
    mask = torch.full((tgt_len, tgt_len), torch.finfo(dtype).min, device=device)
    mask_cond = torch.arange(mask.size(-1), device=device)
    mask.masked_fill_(mask_cond < (mask_cond + 1).view(mask.size(-1), 1), 0)
    mask = mask.to(dtype)

    if past_key_values_length > 0:
        mask = torch.cat([torch.zeros(tgt_len, past_key_values_length, dtype=dtype, device=device), mask], dim=-1)
    return mask[None, None, :, :].expand(bsz, 1, tgt_len, tgt_len + past_key_values_length)


@dataclass
@auto_docstring(
    custom_intro="""
    Base class for text model's outputs that also contains a pooling of the last hidden states.
    """
)
class Kosmos2ModelOutput(ModelOutput):
    r"""
    past_key_values (`Cache`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
        It is a [`~cache_utils.Cache`] instance. For more details, see our [kv cache guide](https://huggingface.co/docs/transformers/en/kv_cache).

        Contains pre-computed hidden-states (key and values in the self-attention blocks and optionally if
        `config.is_encoder_decoder=True` in the cross-attention blocks) that can be used (see `past_key_values`
        input) to speed up sequential decoding.
    image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
        Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.
    projection_attentions (`tuple(torch.FloatTensor)`, *optional*):
        Tuple of `torch.FloatTensor` (one for each layer) of shape `(batch_size, num_heads, sequence_length,
        sequence_length)`.

        Attentions weights given by `Kosmos2ImageToTextProjection`, after the attention softmax, used to compute
        the weighted average in the self-attention heads.
    vision_model_output (`BaseModelOutputWithPooling`, *optional*):
        The output of the [`Kosmos2VisionModel`].
    """

    last_hidden_state: Optional[torch.FloatTensor] = None
    past_key_values: Optional[Cache] = None
    hidden_states: Optional[tuple[torch.FloatTensor]] = None
    attentions: Optional[tuple[torch.FloatTensor]] = None
    image_embeds: Optional[torch.FloatTensor] = None
    projection_attentions: Optional[tuple[torch.FloatTensor]] = None
    vision_model_output: BaseModelOutputWithPooling = None

    def to_tuple(self) -> tuple[Any]:
        return tuple(
            self[k] if k not in ["text_model_output", "vision_model_output"] else getattr(self, k).to_tuple()
            for k in self.keys()
        )


@dataclass
@auto_docstring(
    custom_intro="""
    Model output class for `Kosmos2ForConditionalGeneration`.
    """
)
class Kosmos2ForConditionalGenerationModelOutput(ModelOutput):
    r"""
    loss (`torch.FloatTensor` of shape `(1,)`, *optional*, returned when `labels` is provided):
        Language modeling loss (for next-token prediction).
    logits (`torch.FloatTensor` of shape `(batch_size, sequence_length, config.vocab_size)`):
        Prediction scores of the language modeling head (scores for each vocabulary token before SoftMax).
    past_key_values (`Cache`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
        It is a [`~cache_utils.Cache`] instance. For more details, see our [kv cache guide](https://huggingface.co/docs/transformers/en/kv_cache).

        Contains pre-computed hidden-states (key and values in the self-attention blocks and optionally if
        `config.is_encoder_decoder=True` in the cross-attention blocks) that can be used (see `past_key_values`
        input) to speed up sequential decoding.
    image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
        Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.
    projection_attentions (`tuple(torch.FloatTensor)`, *optional*):
        Tuple of `torch.FloatTensor` (one for each layer) of shape `(batch_size, num_heads, sequence_length,
        sequence_length)`.

        Attentions weights given by `Kosmos2ImageToTextProjection`, after the attention softmax, used to compute
        the weighted average in the self-attention heads.
    vision_model_output (`BaseModelOutputWithPooling`, *optional*):
        The output of the [`Kosmos2VisionModel`].
    """

    loss: Optional[torch.FloatTensor] = None
    logits: Optional[torch.FloatTensor] = None
    past_key_values: Optional[Cache] = None
    hidden_states: Optional[tuple[torch.FloatTensor]] = None
    attentions: Optional[tuple[torch.FloatTensor]] = None
    image_embeds: Optional[torch.FloatTensor] = None
    projection_attentions: Optional[tuple[torch.FloatTensor]] = None
    vision_model_output: BaseModelOutputWithPooling = None

    def to_tuple(self) -> tuple[Any]:
        return tuple(
            self[k] if k not in ["text_model_output", "vision_model_output"] else getattr(self, k).to_tuple()
            for k in self.keys()
        )


# Copied from transformers.models.clip.modeling_clip.CLIPVisionEmbeddings with CLIP->Kosmos2
class Kosmos2VisionEmbeddings(nn.Module):
    def __init__(self, config: Kosmos2VisionConfig):
        super().__init__()
        self.config = config
        self.embed_dim = config.hidden_size
        self.image_size = config.image_size
        self.patch_size = config.patch_size

        self.class_embedding = nn.Parameter(torch.randn(self.embed_dim))

        self.patch_embedding = nn.Conv2d(
            in_channels=config.num_channels,
            out_channels=self.embed_dim,
            kernel_size=self.patch_size,
            stride=self.patch_size,
            bias=False,
        )

        self.num_patches = (self.image_size // self.patch_size) ** 2
        self.num_positions = self.num_patches + 1
        self.position_embedding = nn.Embedding(self.num_positions, self.embed_dim)
        self.register_buffer("position_ids", torch.arange(self.num_positions).expand((1, -1)), persistent=False)

    def interpolate_pos_encoding(self, embeddings: torch.Tensor, height: int, width: int) -> torch.Tensor:
        """
        This method allows to interpolate the pre-trained position encodings, to be able to use the model on higher resolution
        images. This method is also adapted to support torch.jit tracing.

        Adapted from:
        - https://github.com/facebookresearch/dino/blob/de9ee3df6cf39fac952ab558447af1fa1365362a/vision_transformer.py#L174-L194, and
        - https://github.com/facebookresearch/dinov2/blob/e1277af2ba9496fbadf7aec6eba56e8d882d1e35/dinov2/models/vision_transformer.py#L179-L211
        """

        num_patches = embeddings.shape[1] - 1
        position_embedding = self.position_embedding.weight.unsqueeze(0)
        num_positions = position_embedding.shape[1] - 1

        # always interpolate when tracing to ensure the exported model works for dynamic input shapes
        if not torch.jit.is_tracing() and num_patches == num_positions and height == width:
            return self.position_embedding(self.position_ids)

        class_pos_embed = position_embedding[:, :1]
        patch_pos_embed = position_embedding[:, 1:]

        dim = embeddings.shape[-1]

        new_height = height // self.patch_size
        new_width = width // self.patch_size

        sqrt_num_positions = torch_int(num_positions**0.5)
        patch_pos_embed = patch_pos_embed.reshape(1, sqrt_num_positions, sqrt_num_positions, dim)
        patch_pos_embed = patch_pos_embed.permute(0, 3, 1, 2)

        patch_pos_embed = nn.functional.interpolate(
            patch_pos_embed,
            size=(new_height, new_width),
            mode="bicubic",
            align_corners=False,
        )

        patch_pos_embed = patch_pos_embed.permute(0, 2, 3, 1).view(1, -1, dim)

        return torch.cat((class_pos_embed, patch_pos_embed), dim=1)

    def forward(self, pixel_values: torch.FloatTensor, interpolate_pos_encoding=False) -> torch.Tensor:
        batch_size, _, height, width = pixel_values.shape
        if not interpolate_pos_encoding and (height != self.image_size or width != self.image_size):
            raise ValueError(
                f"Input image size ({height}*{width}) doesn't match model ({self.image_size}*{self.image_size})."
            )
        target_dtype = self.patch_embedding.weight.dtype
        patch_embeds = self.patch_embedding(pixel_values.to(dtype=target_dtype))  # shape = [*, width, grid, grid]
        patch_embeds = patch_embeds.flatten(2).transpose(1, 2)

        class_embeds = self.class_embedding.expand(batch_size, 1, -1)
        embeddings = torch.cat([class_embeds, patch_embeds], dim=1)
        if interpolate_pos_encoding:
            embeddings = embeddings + self.interpolate_pos_encoding(embeddings, height, width)
        else:
            embeddings = embeddings + self.position_embedding(self.position_ids)
        return embeddings


# Adapted from transformers.models.siglip.modeling_siglip.eager_attention_forward -> Kosmos2 doesn't cast attn weights to fp32
def eager_attention_forward(
    module: nn.Module,
    query: torch.Tensor,
    key: torch.Tensor,
    value: torch.Tensor,
    attention_mask: Optional[torch.Tensor],
    scaling: float,
    dropout: float = 0.0,
    **kwargs,
):
    attn_weights = torch.matmul(query, key.transpose(-1, -2)) * scaling
    if attention_mask is not None:
        attn_weights = attn_weights + attention_mask

    attn_weights = nn.functional.softmax(attn_weights, dim=-1)
    attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)

    attn_output = torch.matmul(attn_weights, value)
    attn_output = attn_output.transpose(1, 2).contiguous()
    return attn_output, attn_weights


class Kosmos2VisionAttention(nn.Module):
    """Multi-headed attention from 'Attention Is All You Need' paper"""

    def __init__(self, config):
        super().__init__()
        self.config = config
        self.embed_dim = config.hidden_size
        self.num_heads = config.num_attention_heads
        self.head_dim = self.embed_dim // self.num_heads
        if self.head_dim * self.num_heads != self.embed_dim:
            raise ValueError(
                f"embed_dim must be divisible by num_heads (got `embed_dim`: {self.embed_dim} and `num_heads`:"
                f" {self.num_heads})."
            )
        self.scale = self.head_dim**-0.5
        self.dropout = config.attention_dropout
        self.is_causal = False

        self.k_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.v_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.q_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.out_proj = nn.Linear(self.embed_dim, self.embed_dim)

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        causal_attention_mask: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = False,
    ) -> tuple[torch.Tensor, Optional[torch.Tensor]]:
        """Input shape: Batch x Time x Channel"""

        batch_size, seq_length, embed_dim = hidden_states.shape

        queries = self.q_proj(hidden_states)
        keys = self.k_proj(hidden_states)
        values = self.v_proj(hidden_states)

        queries = queries.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
        keys = keys.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
        values = values.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
        # CLIP text model uses both `causal_attention_mask` and `attention_mask`
        # in case FA2 kernel is called, `is_causal` should be inferred from `causal_attention_mask`
        if self.config._attn_implementation != "flash_attention_2":
            if attention_mask is not None and causal_attention_mask is not None:
                attention_mask = attention_mask + causal_attention_mask
            elif causal_attention_mask is not None:
                attention_mask = causal_attention_mask
        else:
            self.is_causal = causal_attention_mask is not None

        attention_interface: Callable = eager_attention_forward
        if self.config._attn_implementation != "eager":
            attention_interface = ALL_ATTENTION_FUNCTIONS[self.config._attn_implementation]

        attn_output, attn_weights = attention_interface(
            self,
            queries,
            keys,
            values,
            attention_mask,
            is_causal=self.is_causal,
            scaling=self.scale,
            dropout=0.0 if not self.training else self.dropout,
        )

        attn_output = attn_output.reshape(batch_size, seq_length, embed_dim).contiguous()
        attn_output = self.out_proj(attn_output)
        if not output_attentions:
            attn_weights = None
        return attn_output, attn_weights


# Copied from transformers.models.clip.modeling_clip.CLIPMLP with CLIP->Kosmos2Vision
class Kosmos2VisionMLP(nn.Module):
    def __init__(self, config):
        super().__init__()
        self.config = config
        self.activation_fn = ACT2FN[config.hidden_act]
        self.fc1 = nn.Linear(config.hidden_size, config.intermediate_size)
        self.fc2 = nn.Linear(config.intermediate_size, config.hidden_size)

    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
        hidden_states = self.fc1(hidden_states)
        hidden_states = self.activation_fn(hidden_states)
        hidden_states = self.fc2(hidden_states)
        return hidden_states


# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoderLayer with AltCLIP->Kosmos2Vision
class Kosmos2VisionEncoderLayer(GradientCheckpointingLayer):
    def __init__(self, config: Kosmos2VisionConfig):
        super().__init__()
        self.embed_dim = config.hidden_size
        self.self_attn = Kosmos2VisionAttention(config)
        self.layer_norm1 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
        self.mlp = Kosmos2VisionMLP(config)
        self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: torch.Tensor,
        causal_attention_mask: torch.Tensor,
        output_attentions: Optional[bool] = False,
    ) -> tuple[torch.FloatTensor]:
        """
        Args:
            hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)`
            attention_mask (`torch.FloatTensor`): attention mask of size
                `(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
                `(config.encoder_attention_heads,)`.
            output_attentions (`bool`, *optional*):
                Whether or not to return the attentions tensors of all attention layers. See `attentions` under
                returned tensors for more detail.
        """
        residual = hidden_states

        hidden_states = self.layer_norm1(hidden_states)
        hidden_states, attn_weights = self.self_attn(
            hidden_states=hidden_states,
            attention_mask=attention_mask,
            causal_attention_mask=causal_attention_mask,
            output_attentions=output_attentions,
        )
        hidden_states = residual + hidden_states

        residual = hidden_states
        hidden_states = self.layer_norm2(hidden_states)
        hidden_states = self.mlp(hidden_states)
        hidden_states = residual + hidden_states

        outputs = (hidden_states,)

        if output_attentions:
            outputs += (attn_weights,)

        return outputs


# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoder with AltCLIP->Kosmos2Vision
class Kosmos2VisionEncoder(nn.Module):
    """
    Transformer encoder consisting of `config.num_hidden_layers` self attention layers. Each layer is a
    [`Kosmos2VisionEncoderLayer`].

    Args:
        config: Kosmos2VisionConfig
    """

    def __init__(self, config: Kosmos2VisionConfig):
        super().__init__()
        self.config = config
        self.layers = nn.ModuleList([Kosmos2VisionEncoderLayer(config) for _ in range(config.num_hidden_layers)])
        self.gradient_checkpointing = False

    @can_return_tuple
    def forward(
        self,
        inputs_embeds,
        attention_mask: Optional[torch.Tensor] = None,
        causal_attention_mask: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        return_dict: Optional[bool] = None,
    ) -> Union[tuple, BaseModelOutput]:
        r"""
        Args:
            inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`):
                Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation.
                This is useful if you want more control over how to convert `input_ids` indices into associated vectors
                than the model's internal embedding lookup matrix.
            attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
                Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:

                - 1 for tokens that are **not masked**,
                - 0 for tokens that are **masked**.

                [What are attention masks?](../glossary#attention-mask)
            causal_attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
                Causal mask for the text model. Mask values selected in `[0, 1]`:

                - 1 for tokens that are **not masked**,
                - 0 for tokens that are **masked**.

                [What are attention masks?](../glossary#attention-mask)
            output_attentions (`bool`, *optional*):
                Whether or not to return the attentions tensors of all attention layers. See `attentions` under
                returned tensors for more detail.
            output_hidden_states (`bool`, *optional*):
                Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors
                for more detail.
            return_dict (`bool`, *optional*):
                Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
        """
        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
        output_hidden_states = (
            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
        )
        return_dict = return_dict if return_dict is not None else self.config.use_return_dict

        encoder_states = () if output_hidden_states else None
        all_attentions = () if output_attentions else None

        hidden_states = inputs_embeds
        for idx, encoder_layer in enumerate(self.layers):
            if output_hidden_states:
                encoder_states = encoder_states + (hidden_states,)
            layer_outputs = encoder_layer(
                hidden_states,
                attention_mask,
                causal_attention_mask,
                output_attentions=output_attentions,
            )

            hidden_states = layer_outputs[0]

            if output_attentions:
                all_attentions = all_attentions + (layer_outputs[1],)

        if output_hidden_states:
            encoder_states = encoder_states + (hidden_states,)

        return BaseModelOutput(
            last_hidden_state=hidden_states, hidden_states=encoder_states, attentions=all_attentions
        )


# Similar to `transformers.models.clip.modeling_clip.CLIPVisionTransformer` but without docstring for `forward`
class Kosmos2VisionTransformer(nn.Module):
    # Copied from transformers.models.altclip.modeling_altclip.AltCLIPVisionTransformer.__init__ with AltCLIPVision->Kosmos2Vision,ALTCLIP_VISION->KOSMOS2_VISION,AltCLIP->Kosmos2Vision
    def __init__(self, config: Kosmos2VisionConfig):
        super().__init__()
        self.config = config
        embed_dim = config.hidden_size

        self.embeddings = Kosmos2VisionEmbeddings(config)
        self.pre_layrnorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
        self.encoder = Kosmos2VisionEncoder(config)
        self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)

    def forward(
        self,
        pixel_values: Optional[torch.FloatTensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        interpolate_pos_encoding: bool = False,
        return_dict: Optional[bool] = None,
    ) -> Union[tuple, BaseModelOutputWithPooling]:
        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
        output_hidden_states = (
            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
        )
        return_dict = return_dict if return_dict is not None else self.config.use_return_dict

        if pixel_values is None:
            raise ValueError("You have to specify pixel_values")

        hidden_states = self.embeddings(pixel_values, interpolate_pos_encoding=interpolate_pos_encoding)
        hidden_states = self.pre_layrnorm(hidden_states)

        encoder_outputs = self.encoder(
            inputs_embeds=hidden_states,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=return_dict,
        )

        last_hidden_state = encoder_outputs[0]
        pooled_output = last_hidden_state[:, 0, :]
        pooled_output = self.post_layernorm(pooled_output)

        if not return_dict:
            return (last_hidden_state, pooled_output) + encoder_outputs[1:]

        return BaseModelOutputWithPooling(
            last_hidden_state=last_hidden_state,
            pooler_output=pooled_output,
            hidden_states=encoder_outputs.hidden_states,
            attentions=encoder_outputs.attentions,
        )


# Similar to `transformers.models.m2m_100.modeling_m2m_100.M2M100SinusoidalPositionalEmbedding` but allowing to pass `position_ids`
class Kosmos2TextSinusoidalPositionalEmbedding(nn.Module):
    """This module produces sinusoidal positional embeddings of any length."""

    # Copied from transformers.models.m2m_100.modeling_m2m_100.M2M100SinusoidalPositionalEmbedding.__init__
    def __init__(self, num_positions: int, embedding_dim: int, padding_idx: Optional[int] = None):
        super().__init__()
        self.offset = 2
        self.embedding_dim = embedding_dim
        self.padding_idx = padding_idx
        self.make_weights(num_positions + self.offset, embedding_dim, padding_idx)

    # Copied from transformers.models.m2m_100.modeling_m2m_100.M2M100SinusoidalPositionalEmbedding.make_weights
    def make_weights(self, num_embeddings: int, embedding_dim: int, padding_idx: Optional[int] = None):
        emb_weights = self.get_embedding(num_embeddings, embedding_dim, padding_idx)
        if hasattr(self, "weights"):
            # in forward put the weights on the correct dtype and device of the param
            emb_weights = emb_weights.to(dtype=self.weights.dtype, device=self.weights.device)

        self.register_buffer("weights", emb_weights, persistent=False)

    @staticmethod
    # Copied from transformers.models.m2m_100.modeling_m2m_100.M2M100SinusoidalPositionalEmbedding.get_embedding
    def get_embedding(num_embeddings: int, embedding_dim: int, padding_idx: Optional[int] = None):
        """
        Build sinusoidal embeddings.

        This matches the implementation in tensor2tensor, but differs slightly from the description in Section 3.5 of
        "Attention Is All You Need".
        """
        half_dim = embedding_dim // 2
        emb = math.log(10000) / (half_dim - 1)
        emb = torch.exp(torch.arange(half_dim, dtype=torch.int64).float() * -emb)
        emb = torch.arange(num_embeddings, dtype=torch.int64).float().unsqueeze(1) * emb.unsqueeze(0)
        emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1).view(num_embeddings, -1)
        if embedding_dim % 2 == 1:
            # zero pad
            emb = torch.cat([emb, torch.zeros(num_embeddings, 1)], dim=1)
        if padding_idx is not None:
            emb[padding_idx, :] = 0

        return emb.to(torch.get_default_dtype())

    @torch.no_grad()
    def forward(
        self,
        input_ids: Optional[torch.Tensor] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        past_key_values_length: int = 0,
        position_ids: Optional[torch.Tensor] = None,
    ):
        if input_ids is not None:
            bsz, seq_len = input_ids.size()
            if position_ids is None:
                # Create the position ids from the input token ids. Any padded tokens remain padded.
                position_ids = self.create_position_ids_from_input_ids(
                    input_ids, self.padding_idx, past_key_values_length
                ).to(input_ids.device)
        else:
            bsz, seq_len = inputs_embeds.size()[:-1]
            if position_ids is None:
                position_ids = self.create_position_ids_from_inputs_embeds(
                    inputs_embeds, past_key_values_length, self.padding_idx
                )

        # expand embeddings if needed
        max_pos = self.padding_idx + 1 + seq_len + past_key_values_length
        if max_pos > self.weights.size(0):
            self.make_weights(max_pos + self.offset, self.embedding_dim, self.padding_idx)

        return self.weights.index_select(0, position_ids.view(-1)).view(bsz, seq_len, self.weights.shape[-1]).detach()

    @staticmethod
    # Copied from transformers.models.m2m_100.modeling_m2m_100.M2M100SinusoidalPositionalEmbedding.create_position_ids_from_inputs_embeds
    def create_position_ids_from_inputs_embeds(inputs_embeds, past_key_values_length, padding_idx):
        """
        We are provided embeddings directly. We cannot infer which are padded so just generate sequential position ids.

        Args:
            inputs_embeds: torch.Tensor

        Returns: torch.Tensor
        """
        input_shape = inputs_embeds.size()[:-1]
        sequence_length = input_shape[1]

        position_ids = torch.arange(
            padding_idx + 1, sequence_length + padding_idx + 1, dtype=torch.long, device=inputs_embeds.device
        )
        return position_ids.unsqueeze(0).expand(input_shape).contiguous() + past_key_values_length

    @staticmethod
    # Copied from transformers.models.roberta.modeling_roberta.RobertaEmbeddings.create_position_ids_from_input_ids
    def create_position_ids_from_input_ids(input_ids, padding_idx, past_key_values_length=0):
        """
        Replace non-padding symbols with their position numbers. Position numbers begin at padding_idx+1. Padding symbols
        are ignored. This is modified from fairseq's `utils.make_positions`.

        Args:
            x: torch.Tensor x:

        Returns: torch.Tensor
        """
        # The series of casts and type-conversions here are carefully balanced to both work with ONNX export and XLA.
        mask = input_ids.ne(padding_idx).int()
        incremental_indices = (torch.cumsum(mask, dim=1).type_as(mask) + past_key_values_length) * mask
        return incremental_indices.long() + padding_idx


class KosmosTextAttention(nn.Module):
    """Multi-headed attention from 'Attention Is All You Need' paper"""

    # Similar to transformers.models.bart.modeling_bart.BartAttention.__init__ except an additional `inner_attn_ln`.
    def __init__(
        self,
        config,
        embed_dim: int,
        num_heads: int,
        dropout: float = 0.0,
        is_decoder: Optional[bool] = False,
        add_inner_attn_layernorm: Optional[bool] = False,
        bias: Optional[bool] = True,
        layer_idx: Optional[bool] = None,
    ):
        super().__init__()
        self.config = config
        self.embed_dim = embed_dim
        self.num_heads = num_heads
        self.dropout = dropout
        self.head_dim = embed_dim // num_heads
        self.is_causal = True

        if (self.head_dim * num_heads) != self.embed_dim:
            raise ValueError(
                f"embed_dim must be divisible by num_heads (got `embed_dim`: {self.embed_dim}"
                f" and `num_heads`: {num_heads})."
            )
        self.scaling = self.head_dim**-0.5
        self.is_decoder = is_decoder
        self.layer_idx = layer_idx

        self.k_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
        self.v_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
        self.q_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
        self.out_proj = nn.Linear(embed_dim, embed_dim, bias=bias)

        # End opy
        self.inner_attn_ln = None
        if add_inner_attn_layernorm:
            self.inner_attn_ln = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)

    def forward(
        self,
        hidden_states: torch.Tensor,
        encoder_hidden_states: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        attention_mask: Optional[torch.Tensor] = None,
        output_attentions: bool = False,
        cache_position: Optional[torch.Tensor] = None,
        **kwargs,
    ) -> tuple[torch.Tensor, Optional[torch.Tensor], Optional[Cache]]:
        """Input shape: Batch x Time x Channel"""

        # if key_value_states are provided this layer is used as a cross-attention layer
        # for the decoder
        is_cross_attention = encoder_hidden_states is not None
        batch_size, seq_length = hidden_states.shape[:2]

        query_states = self.q_proj(hidden_states)
        query_states = query_states.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)

        is_updated = False
        if past_key_values is not None:
            if isinstance(past_key_values, EncoderDecoderCache):
                is_updated = past_key_values.is_updated.get(self.layer_idx)
                if is_cross_attention:
                    # after the first generated id, we can subsequently re-use all key/value_states from cache
                    curr_past_key_values = past_key_values.cross_attention_cache
                else:
                    curr_past_key_values = past_key_values.self_attention_cache
            else:
                curr_past_key_values = past_key_values

        current_states = encoder_hidden_states if is_cross_attention else hidden_states
        if is_cross_attention and past_key_values is not None and is_updated:
            # reuse k,v, cross_attentions
            key_states = curr_past_key_values.layers[self.layer_idx].keys
            value_states = curr_past_key_values.layers[self.layer_idx].values
        else:
            key_states = self.k_proj(current_states)
            value_states = self.v_proj(current_states)
            key_states = key_states.view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)
            value_states = value_states.view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)

            if past_key_values is not None:
                # save all key/value_states to cache to be re-used for fast auto-regressive generation
                cache_position = cache_position if not is_cross_attention else None
                key_states, value_states = curr_past_key_values.update(
                    key_states, value_states, self.layer_idx, {"cache_position": cache_position}
                )
                # set flag that curr layer for cross-attn is already updated so we can re-use in subsequent calls
                if is_cross_attention and isinstance(past_key_values, EncoderDecoderCache):
                    past_key_values.is_updated[self.layer_idx] = True

        attention_interface: Callable = eager_attention_forward

        if self.config._attn_implementation != "eager":
            attention_interface = ALL_ATTENTION_FUNCTIONS[self.config._attn_implementation]

        attn_output, attn_weights = attention_interface(
            self,
            query_states,
            key_states,
            value_states,
            attention_mask,
            dropout=0.0 if not self.training else self.dropout,
            scaling=self.scaling,
            **kwargs,
        )

        attn_output = attn_output.reshape(batch_size, seq_length, -1).contiguous()
        if self.inner_attn_ln is not None:
            attn_output = self.inner_attn_ln(attn_output)

        attn_output = self.out_proj(attn_output)

        return attn_output, attn_weights


class Kosmos2TextFFN(nn.Module):
    def __init__(self, config: Kosmos2TextConfig):
        super().__init__()

        self.dropout = config.dropout
        self.activation_fn = ACT2FN[config.activation_function]
        self.activation_dropout = config.activation_dropout

        self.fc1 = nn.Linear(config.embed_dim, config.ffn_dim)
        self.fc2 = nn.Linear(config.ffn_dim, config.embed_dim)

        self.ffn_layernorm = nn.LayerNorm(config.ffn_dim, eps=config.layer_norm_eps)

    def forward(self, hidden_states):
        hidden_states = self.activation_fn(self.fc1(hidden_states))
        hidden_states = nn.functional.dropout(hidden_states, p=self.activation_dropout, training=self.training)
        hidden_states = self.ffn_layernorm(hidden_states)
        hidden_states = self.fc2(hidden_states)
        hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)

        return hidden_states


class Kosmos2TextBlock(GradientCheckpointingLayer):
    def __init__(self, config: Kosmos2TextConfig, layer_idx=None):
        super().__init__()
        self.embed_dim = config.embed_dim

        self.self_attn = KosmosTextAttention(
            config,
            embed_dim=self.embed_dim,
            num_heads=config.attention_heads,
            dropout=config.attention_dropout,
            is_decoder=True,
            add_inner_attn_layernorm=True,
            layer_idx=layer_idx,
        )
        self.dropout = config.dropout
        self.self_attn_layer_norm = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)

        if config.add_cross_attention:
            self.encoder_attn = KosmosTextAttention(
                config,
                embed_dim=self.embed_dim,
                num_heads=config.attention_heads,
                dropout=config.attention_dropout,
                is_decoder=True,
                add_inner_attn_layernorm=False,
                layer_idx=layer_idx,
            )
            self.encoder_attn_layer_norm = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)

        self.ffn = Kosmos2TextFFN(config)
        self.final_layer_norm = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        encoder_hidden_states: Optional[torch.Tensor] = None,
        encoder_attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        output_attentions: Optional[bool] = False,
        use_cache: Optional[bool] = True,
        cache_position: Optional[torch.Tensor] = None,
        **kwargs,
    ) -> tuple[torch.FloatTensor, Optional[tuple[torch.FloatTensor, torch.FloatTensor]]]:
        residual = hidden_states
        hidden_states = self.self_attn_layer_norm(hidden_states)

        hidden_states, self_attn_weights = self.self_attn(
            hidden_states=hidden_states,
            past_key_values=past_key_values,
            attention_mask=attention_mask,
            output_attentions=output_attentions,
            cache_position=cache_position,
            **kwargs,
        )
        hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
        hidden_states = residual + hidden_states

        # Cross-Attention Block
        cross_attn_weights = None
        if encoder_hidden_states is not None:
            if not hasattr(self, "encoder_attn"):
                raise ValueError(
                    f"If `encoder_hidden_states` are passed, {self} has to be instantiated with cross-attention layers"
                    " by setting `config.add_cross_attention=True`"
                )

            residual = hidden_states
            hidden_states = self.encoder_attn_layer_norm(hidden_states)

            hidden_states, cross_attn_weights = self.encoder_attn(
                hidden_states=hidden_states,
                encoder_hidden_states=encoder_hidden_states,
                attention_mask=encoder_attention_mask,
                past_key_values=past_key_values,
                output_attentions=output_attentions,
                cache_position=cache_position,
                **kwargs,
            )
            hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
            hidden_states = residual + hidden_states

        # Fully Connected
        residual = hidden_states

        hidden_states = self.final_layer_norm(hidden_states)

        # FFN
        hidden_states = self.ffn(hidden_states)
        hidden_states = residual + hidden_states

        outputs = (hidden_states,)

        if output_attentions:
            outputs += (self_attn_weights, cross_attn_weights)
        return outputs


class Kosmos2TextTransformer(nn.Module):
    """
    Transformer decoder consisting of `config.layers` layers. Each layer is a [`Kosmos2TextBlock`].

    Args:
        config: Kosmos2TextConfig
    """

    def __init__(self, config: Kosmos2TextConfig):
        super().__init__()
        self.config = config
        self.dropout = config.dropout
        self.layerdrop = config.layerdrop

        self.embed_scale = math.sqrt(config.embed_dim) if config.scale_embedding else 1.0
        self.embed_tokens = nn.Embedding(config.vocab_size, config.embed_dim, padding_idx=config.pad_token_id)

        self.embed_positions = Kosmos2TextSinusoidalPositionalEmbedding(
            num_positions=config.max_position_embeddings,
            embedding_dim=config.embed_dim,
            padding_idx=config.pad_token_id,
        )

        self.layers = nn.ModuleList([Kosmos2TextBlock(config, layer_idx=i) for i in range(config.layers)])
        self.layer_norm = nn.LayerNorm(config.embed_dim, config.layer_norm_eps)

        self.gradient_checkpointing = False

    def _prepare_decoder_attention_mask(self, attention_mask, input_shape, inputs_embeds, past_key_values_length):
        # create causal mask
        # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
        combined_attention_mask = None
        if input_shape[-1] > 1:
            combined_attention_mask = _make_causal_mask(
                input_shape,
                inputs_embeds.dtype,
                device=inputs_embeds.device,
                past_key_values_length=past_key_values_length,
            )

        if attention_mask is not None:
            # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
            expanded_attn_mask = _expand_mask(attention_mask, inputs_embeds.dtype, tgt_len=input_shape[-1]).to(
                inputs_embeds.device
            )
            combined_attention_mask = (
                expanded_attn_mask if combined_attention_mask is None else expanded_attn_mask + combined_attention_mask
            )

        return combined_attention_mask

    def forward_embedding(
        self,
        input_ids,
        inputs_embeds: Optional[torch.Tensor] = None,
        image_embeds: Optional[torch.Tensor] = None,
        img_input_mask: Optional[torch.Tensor] = None,
        past_key_values_length: int = 0,
        position_ids: Optional[torch.Tensor] = None,
    ):
        # The argument `inputs_embeds` should be the one without being multiplied by `self.embed_scale`.
        if inputs_embeds is None:
            inputs_embeds = self.embed_tokens(input_ids)

        if image_embeds is not None:
            inputs_embeds[img_input_mask.to(dtype=torch.bool)] = image_embeds.to(inputs_embeds.device).view(
                -1, image_embeds.size(-1)
            )

        inputs_embeds = inputs_embeds * self.embed_scale

        # embed positions
        positions = self.embed_positions(
            input_ids=input_ids,
            inputs_embeds=inputs_embeds,
            past_key_values_length=past_key_values_length,
            position_ids=position_ids,
        )
        positions = positions.to(inputs_embeds.device)

        hidden_states = inputs_embeds + positions

        hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)

        return hidden_states

    def forward(
        self,
        input_ids: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        image_embeds: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        encoder_hidden_states: Optional[torch.Tensor] = None,
        encoder_attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        return_dict: Optional[bool] = None,
        cache_position: Optional[torch.Tensor] = None,
        **kwargs: Unpack[FlashAttentionKwargs],
    ) -> Union[tuple, BaseModelOutputWithPastAndCrossAttentions]:
        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
        output_hidden_states = (
            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
        )
        use_cache = use_cache if use_cache is not None else self.config.use_cache

        if input_ids is not None and inputs_embeds is not None:
            raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time")
        elif input_ids is not None:
            input_shape = input_ids.shape
            input_ids = input_ids.view(-1, input_shape[-1])
        elif inputs_embeds is not None:
            input_shape = inputs_embeds.size()[:-1]
        else:
            raise ValueError("You have to specify either input_ids or inputs_embeds")

        if self.gradient_checkpointing and self.training:
            if use_cache:
                logger.warning_once(
                    "`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
                )
                use_cache = False

        if use_cache and past_key_values is None:
            past_key_values = (
                EncoderDecoderCache(DynamicCache(config=self.config), DynamicCache(config=self.config))
                if encoder_hidden_states is not None or self.config.is_encoder_decoder
                else DynamicCache(config=self.config)
            )

        past_key_values_length = past_key_values.get_seq_length() if past_key_values is not None else 0

        # We don't need img info. when `past_key_values_length` > 0
        if past_key_values_length > 0:
            image_embeds = None
            image_embeds_position_mask = None

        hidden_states = self.forward_embedding(
            input_ids=input_ids,
            inputs_embeds=inputs_embeds,
            image_embeds=image_embeds,
            img_input_mask=image_embeds_position_mask,
            past_key_values_length=past_key_values_length,
            position_ids=position_ids,
        )

        attention_mask = self._prepare_decoder_attention_mask(
            attention_mask, input_shape, hidden_states, past_key_values_length
        )

        # expand encoder attention mask
        if encoder_hidden_states is not None and encoder_attention_mask is not None:
            # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
            encoder_attention_mask = _expand_mask(encoder_attention_mask, inputs_embeds.dtype, tgt_len=input_shape[-1])

        hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)

        # decoder layers
        all_hidden_states = () if output_hidden_states else None
        all_self_attns = () if output_attentions else None
        all_cross_attentions = () if (output_attentions and encoder_hidden_states is not None) else None

        for idx, decoder_layer in enumerate(self.layers):
            # add LayerDrop (see https://huggingface.co/papers/1909.11556 for description)
            if output_hidden_states:
                all_hidden_states += (hidden_states,)
            if self.training:
                dropout_probability = torch.rand([])
                if dropout_probability < self.layerdrop:
                    continue

            layer_outputs = decoder_layer(
                hidden_states,
                attention_mask,
                encoder_hidden_states,
                encoder_attention_mask=encoder_attention_mask,
                past_key_values=past_key_values,
                output_attentions=output_attentions,
                use_cache=use_cache,
                cache_position=cache_position,
                **kwargs,
            )
            hidden_states = layer_outputs[0]

            if output_attentions:
                all_self_attns += (layer_outputs[1],)

                if encoder_hidden_states is not None:
                    all_cross_attentions += (layer_outputs[2],)

        # add final layer norm
        hidden_states = self.layer_norm(hidden_states)

        # add hidden states from the last decoder layer
        if output_hidden_states:
            all_hidden_states += (hidden_states,)

        return BaseModelOutputWithPastAndCrossAttentions(
            last_hidden_state=hidden_states,
            past_key_values=past_key_values,
            hidden_states=all_hidden_states,
            attentions=all_self_attns,
            cross_attentions=all_cross_attentions,
        )


@auto_docstring
class Kosmos2PreTrainedModel(PreTrainedModel):
    config: Kosmos2Config
    input_modalities = ["image", "text"]
    supports_gradient_checkpointing = True
    _no_split_modules = ["Kosmos2VisionEncoderLayer", "Kosmos2TextBlock"]
    _supports_attention_backend = True
    _supports_flash_attn = True
    _supports_sdpa = True

    @torch.no_grad()
    def _init_weights(self, module: nn.Module):
        """Initialize the weights"""
        if isinstance(self, Kosmos2VisionModel):
            factor = self.config.initializer_factor
        elif isinstance(self, (Kosmos2Model, Kosmos2ForConditionalGeneration)):
            factor = self.config.vision_config.initializer_factor

        if isinstance(self, (Kosmos2TextModel, Kosmos2TextForCausalLM)):
            std = self.config.init_std
        elif isinstance(self, (Kosmos2Model, Kosmos2ForConditionalGeneration)):
            std = self.config.text_config.init_std

        if isinstance(module, Kosmos2VisionEmbeddings):
            init.normal_(module.class_embedding, mean=0.0, std=module.embed_dim**-0.5 * factor)
            init.normal_(module.patch_embedding.weight, std=module.config.initializer_range * factor)
            init.normal_(module.position_embedding.weight, std=module.config.initializer_range * factor)
        elif isinstance(module, Kosmos2VisionAttention):
            in_proj_std = (module.embed_dim**-0.5) * ((2 * module.config.num_hidden_layers) ** -0.5) * factor
            out_proj_std = (module.embed_dim**-0.5) * factor
            init.normal_(module.q_proj.weight, std=in_proj_std)
            init.normal_(module.k_proj.weight, std=in_proj_std)
            init.normal_(module.v_proj.weight, std=in_proj_std)
            init.normal_(module.out_proj.weight, std=out_proj_std)
        elif isinstance(module, Kosmos2VisionMLP):
            in_proj_std = (module.config.hidden_size**-0.5) * ((2 * module.config.num_hidden_layers) ** -0.5) * factor
            fc_std = (2 * module.config.hidden_size) ** -0.5 * factor
            init.normal_(module.fc1.weight, std=fc_std)
            init.normal_(module.fc2.weight, std=in_proj_std)
        elif isinstance(module, KosmosTextAttention):
            init.normal_(module.q_proj.weight, std=std)
            init.normal_(module.k_proj.weight, std=std)
            init.normal_(module.v_proj.weight, std=std)
            init.normal_(module.out_proj.weight, std=std)
        elif isinstance(module, Kosmos2TextFFN):
            init.normal_(module.fc1.weight, std=std)
            init.normal_(module.fc2.weight, std=std)
        elif isinstance(module, Kosmos2TextForCausalLM):
            init.normal_(module.lm_head.weight, std=std)
        elif isinstance(module, Kosmos2ImageToTextProjection):
            init.normal_(module.dense.weight, std=std)
            init.normal_(module.latent_query)
        elif isinstance(module, Kosmos2TextTransformer):
            init.normal_(module.embed_tokens.weight, mean=0.0, std=std)
            if module.embed_tokens.padding_idx is not None:
                init.zeros_(module.embed_tokens.weight[module.embed_tokens.padding_idx])
        elif isinstance(module, nn.LayerNorm):
            init.ones_(module.weight)
            init.zeros_(module.bias)

        if isinstance(module, nn.Linear) and module.bias is not None:
            init.zeros_(module.bias)


class Kosmos2VisionModel(Kosmos2PreTrainedModel):
    config: Kosmos2VisionConfig
    main_input_name = "pixel_values"
    input_modalities = "image"

    # Copied from transformers.models.clip.modeling_clip.CLIPVisionModel.__init__ with CLIP_VISION->KOSMOS2_VISION,CLIP->Kosmos2,self.vision_model->self.model
    def __init__(self, config: Kosmos2VisionConfig):
        super().__init__(config)
        self.model = Kosmos2VisionTransformer(config)
        # Initialize weights and apply final processing
        self.post_init()

    # Copied from transformers.models.clip.modeling_clip.CLIPVisionModel.get_input_embeddings with CLIP_VISION->KOSMOS2_VISION,CLIP->Kosmos2,self.vision_model->self.model
    def get_input_embeddings(self) -> nn.Module:
        return self.model.embeddings.patch_embedding

    @auto_docstring
    def forward(
        self,
        pixel_values: Optional[torch.FloatTensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        interpolate_pos_encoding: bool = False,
        return_dict: Optional[bool] = None,
    ) -> Union[tuple, BaseModelOutputWithPooling]:
        return self.model(
            pixel_values=pixel_values,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            interpolate_pos_encoding=interpolate_pos_encoding,
            return_dict=return_dict,
        )


class Kosmos2TextModel(Kosmos2PreTrainedModel):
    config: Kosmos2TextConfig
    input_modalities = "text"

    def __init__(self, config: Kosmos2TextConfig):
        super().__init__(config)
        self.model = Kosmos2TextTransformer(config)
        # Initialize weights and apply final processing
        self.post_init()

    def get_input_embeddings(self) -> nn.Module:
        return self.model.embed_tokens

    @can_return_tuple
    @auto_docstring
    def forward(
        self,
        input_ids: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        image_embeds: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        encoder_hidden_states: Optional[torch.Tensor] = None,
        encoder_attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        return_dict: Optional[bool] = None,
        cache_position: Optional[torch.Tensor] = None,
        **kwargs: Unpack[FlashAttentionKwargs],
    ) -> Union[tuple, BaseModelOutputWithPastAndCrossAttentions]:
        r"""
        image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
            Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.
        image_embeds_position_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
            Mask to indicate the location in a sequence to insert the image features . Mask values selected in `[0,
            1]`:

            - 1 for places where to put the image features,
            - 0 for places that are not for image features (i.e. for text tokens).
        """
        return self.model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            encoder_hidden_states=encoder_hidden_states,
            encoder_attention_mask=encoder_attention_mask,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            position_ids=position_ids,
            use_cache=use_cache,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=return_dict,
            cache_position=cache_position,
            **kwargs,
        )


@auto_docstring(
    custom_intro="""
    The text model from KOSMOS-2 with a language modeling head on top (linear layer with weights tied to the input
    embeddings).
    """
)
class Kosmos2TextForCausalLM(Kosmos2PreTrainedModel, GenerationMixin):
    config: Kosmos2TextConfig
    _tied_weights_keys = {"lm_head.weight": "model.embed_tokens.weight"}

    def __init__(self, config: Kosmos2TextConfig):
        super().__init__(config)

        self.model = Kosmos2TextTransformer(config)
        self.lm_head = nn.Linear(in_features=config.embed_dim, out_features=config.vocab_size, bias=False)

        # Initialize weights and apply final processing
        self.post_init()

    def get_input_embeddings(self) -> nn.Module:
        return self.model.embed_tokens

    def get_output_embeddings(self) -> nn.Module:
        return self.lm_head

    @can_return_tuple
    @auto_docstring
    def forward(
        self,
        input_ids: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        image_embeds: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        encoder_hidden_states: Optional[torch.Tensor] = None,
        encoder_attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        labels: Optional[torch.LongTensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        cache_position: Optional[torch.Tensor] = None,
        logits_to_keep: Union[int, torch.Tensor] = 0,
        **kwargs: Unpack[TransformersKwargs],
    ) -> Union[tuple, CausalLMOutputWithCrossAttentions]:
        r"""
        image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
            Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.
        image_embeds_position_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
            Mask to indicate the location in a sequence to insert the image features . Mask values selected in `[0,
            1]`:

            - 1 for places where to put the image features,
            - 0 for places that are not for image features (i.e. for text tokens).
        labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
            Labels for computing the left-to-right language modeling loss (next word prediction). Indices should be in
            `[-100, 0, ..., config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are
            ignored (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`
        """
        if labels is not None:
            if use_cache:
                logger.warning("The `use_cache` argument is changed to `False` since `labels` is provided.")
            use_cache = False

        outputs: BaseModelOutputWithPastAndCrossAttentions = self.model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            encoder_hidden_states=encoder_hidden_states,
            encoder_attention_mask=encoder_attention_mask,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            position_ids=position_ids,
            use_cache=use_cache,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            cache_position=cache_position,
            **kwargs,
        )

        hidden_states = outputs.last_hidden_state
        # Only compute necessary logits, and do not upcast them to float if we are not computing the loss
        slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
        logits = self.lm_head(hidden_states[:, slice_indices, :])

        loss = None
        if labels is not None:
            loss = self.loss_function(logits=logits, labels=labels, vocab_size=self.config.vocab_size, **kwargs)

        return CausalLMOutputWithCrossAttentions(
            loss=loss,
            logits=logits,
            past_key_values=outputs.past_key_values,
            hidden_states=outputs.hidden_states,
            attentions=outputs.attentions,
            cross_attentions=outputs.cross_attentions,
        )

    def prepare_inputs_for_generation(
        self,
        input_ids,
        image_embeds=None,
        image_embeds_position_mask=None,
        past_key_values=None,
        attention_mask=None,
        inputs_embeds=None,
        use_cache=None,
        cache_position=None,
        **model_kwargs,
    ):
        # Overwritten -- in specific circumstances we don't want to forward image inputs to the model

        # If we're in cached decoding stage, pixel values should be None because input ids do not contain special image token anymore
        if cache_position[0] != 0:
            image_embeds = None
            image_embeds_position_mask = None

        # appending `False` to `image_embeds_position_mask` (because `input_ids` grows during generation)
        elif image_embeds_position_mask is not None:
            batch_size, seq_len = inputs_embeds.size()[:-1] if inputs_embeds is not None else input_ids.size()
            mask_len = image_embeds_position_mask.size()[-1]
            image_embeds_position_mask = torch.cat(
                (
                    image_embeds_position_mask,
                    torch.zeros(size=(batch_size, seq_len - mask_len), dtype=torch.bool, device=input_ids.device),
                ),
                dim=1,
            )

        model_inputs = super().prepare_inputs_for_generation(
            input_ids,
            past_key_values=past_key_values,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            inputs_embeds=inputs_embeds,
            use_cache=use_cache,
            cache_position=cache_position,
            **model_kwargs,
        )
        # Kosmos2 has offset for position ids, so we need to create them correctly in PositionEmbedding layer
        model_inputs.pop("position_ids", None)

        return model_inputs


class Kosmos2ImageToTextProjection(nn.Module):
    """The layer that transforms the image model's output to part of the text model's input (namely, image features)"""

    def __init__(self, config: Kosmos2Config):
        super().__init__()
        self.dense = nn.Linear(config.vision_config.hidden_size, config.text_config.embed_dim)
        self.latent_query = nn.Parameter(torch.randn(config.latent_query_num, config.text_config.embed_dim))

        self.x_attn = KosmosTextAttention(
            config.text_config,
            config.text_config.embed_dim,
            config.text_config.attention_heads,
            dropout=config.text_config.attention_dropout,
            is_decoder=False,
            add_inner_attn_layernorm=False,
        )

    def forward(self, features):
        hidden_states = self.dense(features)

        # shape = [batch, latent_query_num, h_dim]
        latent_query = self.latent_query.unsqueeze(0).expand(hidden_states.size(0), -1, -1)
        key_value_states = torch.cat([hidden_states, latent_query], dim=1)

        hidden_states, attn_weights = self.x_attn(
            hidden_states=latent_query,
            encoder_hidden_states=key_value_states,
            past_key_values=None,
            attention_mask=None,
            output_attentions=None,
        )

        return hidden_states, attn_weights


@auto_docstring(
    custom_intro="""
    KOSMOS-2 Model for generating text and image features. The model consists of a vision encoder and a language model.
    """
)
class Kosmos2Model(Kosmos2PreTrainedModel):
    config: Kosmos2Config
    main_input_name = "pixel_values"

    def __init__(self, config: Kosmos2Config):
        super().__init__(config)

        self.text_model = Kosmos2TextModel(config.text_config)
        self.vision_model = Kosmos2VisionModel(config.vision_config)
        self.image_to_text_projection = Kosmos2ImageToTextProjection(config)

        # Initialize weights and apply final processing
        self.post_init()

    def get_input_embeddings(self) -> nn.Module:
        return self.text_model.model.embed_tokens

    def set_input_embeddings(self, value):
        self.text_model.model.embed_tokens = value

    def get_image_features(
        self,
        pixel_values: torch.FloatTensor,
        return_attentions: Optional[bool] = False,
        interpolate_pos_encoding: Optional[bool] = False,
    ):
        """
        Encodes images into continuous embeddings that can be forwarded to the language model.

        Args:
            pixel_values (`torch.FloatTensor` of shape `(batch_size, num_channels, image_size, image_size)`):
                The tensors corresponding to the input images.
            return_attentions (`bool`, *optional*, defaults to `False`):
                Whether to return `projection_attentions` or not.
            interpolate_pos_encoding (`bool`, *optional*, defaults to `False`):
                Whether to interpolate positional embeddings or not.
        """
        vision_model_output = self.vision_model(
            pixel_values=pixel_values,
            interpolate_pos_encoding=interpolate_pos_encoding,
        )
        # The whole `last_hidden_state` through `post_layernorm` instead of just `pooled_output`.
        image_embeds = self.vision_model.model.post_layernorm(vision_model_output[0])
        # normalized features
        image_embeds = nn.functional.normalize(image_embeds, dim=-1)
        image_embeds, projection_attentions = self.image_to_text_projection(image_embeds)

        if return_attentions:
            return image_embeds, projection_attentions
        return image_embeds

    @can_return_tuple
    @auto_docstring
    def forward(
        self,
        pixel_values: Optional[torch.Tensor] = None,
        input_ids: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        image_embeds: Optional[torch.Tensor] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        interpolate_pos_encoding: bool = False,
        return_dict: Optional[bool] = None,
        **kwargs: Unpack[FlashAttentionKwargs],
    ) -> Union[tuple, Kosmos2ModelOutput]:
        r"""
        image_embeds_position_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
            Mask to indicate the location in a sequence to insert the image features . Mask values selected in `[0,
            1]`:

            - 1 for places where to put the image features,
            - 0 for places that are not for image features (i.e. for text tokens).
        image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
            Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.

        Examples:

        ```python
        >>> from PIL import Image
        >>> import requests
        >>> from transformers import AutoProcessor, Kosmos2Model

        >>> model = Kosmos2Model.from_pretrained("microsoft/kosmos-2-patch14-224")
        >>> processor = AutoProcessor.from_pretrained("microsoft/kosmos-2-patch14-224")

        >>> url = "https://huggingface.co/microsoft/kosmos-2-patch14-224/resolve/main/snowman.jpg"
        >>> image = Image.open(requests.get(url, stream=True).raw)

        >>> text = (
        ...     "<grounding> An image of<phrase> a snowman</phrase><object><patch_index_0044><patch_index_0863>"
        ...     "</object> warming himself by<phrase> a fire</phrase><object><patch_index_0005><patch_index_0911>"
        ...     "</object>"
        ... )

        >>> inputs = processor(text=text, images=image, return_tensors="pt", add_eos_token=True)

        >>> last_hidden_state = model(
        ...     pixel_values=inputs["pixel_values"],
        ...     input_ids=inputs["input_ids"],
        ...     attention_mask=inputs["attention_mask"],
        ...     image_embeds_position_mask=inputs["image_embeds_position_mask"],
        ... ).last_hidden_state
        >>> list(last_hidden_state.shape)
        [1, 91, 2048]
        ```"""
        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
        output_hidden_states = (
            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
        )
        return_dict = return_dict if return_dict is not None else self.config.use_return_dict

        vision_model_output = None
        projection_attentions = None
        if image_embeds is None:
            if pixel_values is None:
                raise ValueError("You have to specify either `pixel_values` or `image_embeds`.")
            image_embeds, projection_attentions = self.get_image_features(
                pixel_values, return_attentions=True, interpolate_pos_encoding=interpolate_pos_encoding
            )

        outputs = self.text_model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            position_ids=position_ids,
            use_cache=use_cache,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=True,
            **kwargs,
        )

        return Kosmos2ModelOutput(
            last_hidden_state=outputs.last_hidden_state,
            past_key_values=outputs.past_key_values,
            hidden_states=outputs.hidden_states,
            attentions=outputs.attentions,
            image_embeds=image_embeds,
            projection_attentions=projection_attentions,
            vision_model_output=vision_model_output,
        )


@auto_docstring(
    custom_intro="""
    KOSMOS-2 Model for generating text and bounding boxes given an image. The model consists of a vision encoder and a
    language model.
    """
)
class Kosmos2ForConditionalGeneration(Kosmos2PreTrainedModel, GenerationMixin):
    config: Kosmos2Config
    main_input_name = "pixel_values"
    _tied_weights_keys = {"text_model.lm_head.weight": "text_model.model.embed_tokens.weight"}

    def __init__(self, config: Kosmos2Config):
        super().__init__(config)

        self.text_model = Kosmos2TextForCausalLM(config.text_config)
        self.vision_model = Kosmos2VisionModel(config.vision_config)

        self.image_to_text_projection = Kosmos2ImageToTextProjection(config)

        # Initialize weights and apply final processing
        self.post_init()

    def get_input_embeddings(self) -> nn.Module:
        return self.text_model.model.embed_tokens

    def set_input_embeddings(self, value):
        self.text_model.model.embed_tokens = value

    def get_output_embeddings(self) -> nn.Module:
        return self.text_model.get_output_embeddings()

    def set_output_embeddings(self, new_embeddings):
        self.text_model.set_output_embeddings(new_embeddings)

    @can_return_tuple
    @auto_docstring
    def forward(
        self,
        pixel_values: Optional[torch.Tensor] = None,
        input_ids: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        past_key_values: Optional[Cache] = None,
        image_embeds: Optional[torch.Tensor] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        labels: Optional[torch.LongTensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        logits_to_keep: Union[int, torch.Tensor] = 0,
        **kwargs: Unpack[TransformersKwargs],
    ) -> Union[tuple, Kosmos2ForConditionalGenerationModelOutput]:
        r"""
        image_embeds_position_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
            Mask to indicate the location in a sequence to insert the image features . Mask values selected in `[0,
            1]`:

            - 1 for places where to put the image features,
            - 0 for places that are not for image features (i.e. for text tokens).
        image_embeds (`torch.FloatTensor` of shape `(batch_size, latent_query_num, hidden_size)`, *optional*):
            Sequence of hidden-states at the output of `Kosmos2ImageToTextProjection`.
        labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
            Labels for computing the left-to-right language modeling loss (next word prediction). Indices should be in
            `[-100, 0, ..., config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are
            ignored (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`

        Examples:

        ```python
        >>> from PIL import Image
        >>> import requests
        >>> from transformers import AutoProcessor, Kosmos2ForConditionalGeneration

        >>> model = Kosmos2ForConditionalGeneration.from_pretrained("microsoft/kosmos-2-patch14-224")
        >>> processor = AutoProcessor.from_pretrained("microsoft/kosmos-2-patch14-224")

        >>> url = "https://huggingface.co/microsoft/kosmos-2-patch14-224/resolve/main/snowman.jpg"
        >>> image = Image.open(requests.get(url, stream=True).raw)

        >>> prompt = "<grounding> An image of"

        >>> inputs = processor(text=prompt, images=image, return_tensors="pt")

        >>> generated_ids = model.generate(
        ...     pixel_values=inputs["pixel_values"],
        ...     input_ids=inputs["input_ids"],
        ...     attention_mask=inputs["attention_mask"],
        ...     image_embeds=None,
        ...     image_embeds_position_mask=inputs["image_embeds_position_mask"],
        ...     use_cache=True,
        ...     max_new_tokens=64,
        ... )
        >>> generated_text = processor.batch_decode(generated_ids, skip_special_tokens=True)[0]
        >>> processed_text = processor.post_process_generation(generated_text, cleanup_and_extract=False)
        >>> processed_text
        '<grounding> An image of<phrase> a snowman</phrase><object><patch_index_0044><patch_index_0863></object> warming himself by<phrase> a fire</phrase><object><patch_index_0005><patch_index_0911></object>.'

        >>> caption, entities = processor.post_process_generation(generated_text)
        >>> caption
        'An image of a snowman warming himself by a fire.'

        >>> entities
        [('a snowman', (12, 21), [(0.390625, 0.046875, 0.984375, 0.828125)]), ('a fire', (41, 47), [(0.171875, 0.015625, 0.484375, 0.890625)])]
        ```"""
        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
        output_hidden_states = (
            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
        )

        vision_model_output = None
        projection_attentions = None
        if image_embeds is None:
            if pixel_values is None:
                raise ValueError("You have to specify either `pixel_values` or `image_embeds`.")

            vision_model_output = self.vision_model(
                pixel_values=pixel_values,
                output_attentions=output_attentions,
                output_hidden_states=output_hidden_states,
            )
            # The whole `last_hidden_state` through `post_layernorm` instead of just `pooled_output`.
            image_embeds = self.vision_model.model.post_layernorm(vision_model_output[0])
            # normalized features
            image_embeds = nn.functional.normalize(image_embeds, dim=-1)
            image_embeds, projection_attentions = self.image_to_text_projection(image_embeds)

        lm_outputs: CausalLMOutputWithCrossAttentions = self.text_model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            position_ids=position_ids,
            labels=labels,
            use_cache=use_cache,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            logits_to_keep=logits_to_keep,
            **kwargs,
        )

        return Kosmos2ForConditionalGenerationModelOutput(
            loss=lm_outputs.loss,
            logits=lm_outputs.logits,
            past_key_values=lm_outputs.past_key_values,
            hidden_states=lm_outputs.hidden_states,
            attentions=lm_outputs.attentions,
            image_embeds=image_embeds,
            projection_attentions=projection_attentions,
            vision_model_output=vision_model_output,
        )

    @torch.no_grad()
    def generate(
        self,
        pixel_values: Optional[torch.Tensor] = None,
        image_embeds_position_mask: Optional[torch.Tensor] = None,
        input_ids: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        image_embeds: Optional[torch.Tensor] = None,
        inputs_embeds: Optional[torch.Tensor] = None,
        **kwargs,
    ):
        # in order to allow `inputs` argument (as in `GenerationMixin`)
        inputs = kwargs.pop("inputs", None)
        if pixel_values is not None and inputs is not None:
            raise ValueError(
                f"`inputs`: {inputs} were passed alongside `pixel_values` which is not allowed."
                f"Make sure to either pass `inputs` or pixel_values=..."
            )
        if pixel_values is None and inputs is not None:
            pixel_values = inputs

        if image_embeds is None:
            vision_model_output = self.vision_model(pixel_values)
            # The whole `last_hidden_state` through `post_layernorm` instead of just `pooled_output`.
            image_embeds = self.vision_model.model.post_layernorm(vision_model_output[0])
            # normalized features
            image_embeds = nn.functional.normalize(image_embeds, dim=-1)
            image_embeds, projection_attentions = self.image_to_text_projection(image_embeds)

        output = self.text_model.generate(
            input_ids=input_ids,
            attention_mask=attention_mask,
            image_embeds=image_embeds,
            image_embeds_position_mask=image_embeds_position_mask,
            inputs_embeds=inputs_embeds,
            **kwargs,
        )

        return output


__all__ = ["Kosmos2ForConditionalGeneration", "Kosmos2Model", "Kosmos2PreTrainedModel"]
